I have a 41cc blower that runs great.

Will this make a good conversion?

What after market parts will I need?

What size prop and at what RPM should I expect to run?

Need more information, what brand, how old, etc. Pict's would be good.

Most often, the carbs on blowers have to be changed out with one from a chain saw. The blower carbs are wide open or partial throttle. the don't work good on a model.

Enjoy,

Jim

It's an Echo, model number is PB4500
Serial number 0002103

I'm not sure of the age, but I've had it for a couple of years and it starts and runs good.

For some reason I thought it was a 4100 series motor.

So what do tou guys think?

This is what the plane should look like when It's finnished.
109" wing spand, 71" from front of the cowl to the end of the rudder.

Estamated weight 22 pounds.

I only have one wing to install the servos in and paint both wings and it should fly.

I am guessing that is a cessna right.

Howard DGA

Enjoy,

Jim

It's a 1936 Mr. Mulligan.

It was a pylon racer in it's hay day.

We are both right...
The plane in the picture is not THE MR MULLIGAN. It was destroyed in a air race crash. It had a 850 hp P&W Hornet engine. The plane in your picture is a DGA dressed up ala Mr. Mulligan? Typically the Howard DGA 11 is considered to be a Mulligan but they only have a P&W R985 engine of 450 hp.

If there is a picture below it is of a DGA dressed up to be like a Mr Mulligan but it only has a Pratt and Whitney R1340 single stage blower 550 hp engine where the original had a 2 stage blower. It's in Springdale Arkansas. It was the second actual replica of Mr Mulligan registered as N273Y. The parts of the original Mr Mulligan, NR273Y, were retrieved from NM and used in a replica of Mr Mulligan but it too crashed some years before the replica in this picture.


Enjoy,

Jim

I found your picture on the Web. It is a 1943 Howard DGA15-P with a 450 hp P&W engine. They came out in 1940 and were mostly used by the military originally.

Enjoy,

Jim

The work bench is 36x96", just to give you an idea of it's size.
A scale prop would be 24"
I'm looking for an engine that will power this plane.
I'm told a 46cc Poulan will deliver 30 pounds of thrust.

What can I expect from the 45cc Echo?

The Poulan 46 is about 22-8 max but I'm sure the Echo will take your nice looking Mr Mulligan for a ride. Echo's are very well made.

Enjoy,

Jim

I would use a g 62 and call it a day. I am sure you could pick up a used one for the same as a conversion. That is if you are paying for the engine it self before converting.

That's the thing. I've owned the blower for a couple of years.
It always starts and runs good. I just don't need it anymore.
But if it's marginal then I'll go with the G-62.

The plane should weigh in at 22pounds.

I've been told that this engine should ccarry a 22x8 prop.

I understand that a 22x8 prop at 7000rpm delivers 41 pounds of thrust.

The only thing I should need to buy is a prop hub.

I just need a little more feed back before I make up my mind.

From taking fish scale measurements, a 22 X 8 at 7000 is more like around 27 lbs thrust.

But 15 lb would be plenty for your plane to fly very well.

Enjoy,

Jim

I have a 40cc echo chainsaw engine, I think it is differant from the blower engines, this engine is a Koritz. It will turn a 20-10 at 7000, and it turned the 18-10 at 7800 before I advanced the ignition timing. I have heard from the lawn repair person that I know that the blower engines are high tourqe low rpm engines compaired to the chainsaw engines. STeve

Here are some pictures.

The weight is 4lbs 6oz of that 7 oz is the flywheel.

With the nose of the Mr. Mulligan being so short weight should not be an issue.

I'll put the wings on today and check the CG.

Here is the planr in my front room.

Were checking the CG and the fit of the wing.

Oh yes the wife knows.

New Problem

I just discovered that the Echo 44 run back wards.

I believe I should be able to simply flip the flywheel over to correct this slight over sight.
The shaft is not tapered and the flywheel fits nicely inverted.

Any comments? Any suggestions?

Ralphbf.
I have a 21cc echo from a cutivator that is clockwise also. One simple solution is to mount the prop hub on the other shaft. Yes turn it around. The small flywheel should make it easy to mount the engine with standoffs positioned around the flywheel. This is how the Zenoah G23 is setup with the flywheel is in back next to the fire wall. It makes for a cleaner installation in tight cowls also. This is how I am going to do my 21cc echo.

Dave

The shaft that comes out the back is 15mm that is necked down to 8mm.
It would be a much stronger mount, but I dont know about the strength if the 8mm shaft or the Left Hand threads. They look pretty whimpy to me, plus they don't look like basic mertic threads to me.

But I do have the nut with the dog gears on it to compare.

You do not want to use left hand threads. It will definitely be a problem!

The engine will happily run either way, depending on the ignition timing.

Good luck,
AV8TOR

Magneto ignition,,,,, "run either way" ?

It wont' run the opposite direction unless you retime the flywheel. I did the same thing with a blower motor, was trying to start it backwards while having it mounted inverted, got gas on top the piston, and with the nissan starter that I have, bent the crank before I figured it out.

I have my echo chainsaw engine on a 24lb plane, has plenty of power to fly, not over powered, but flys very well. Steve

Hi,
Check the threads on the flywheel end. I think that they are left handed, so the rotation tightens the nut. The other end of the shaft should be right handed. The picture of that shaft at the impeller end appears to be 8x125mm and has a shoulder. Varify that it is right handed and use it to drive the prop. Pete at Wacker Engines.com made a hub for me with 8x125mm at the shaft and 5/16x24 at the prop. I sent the nut to him to ensure the right size. It is knurled at both ends and has a large prop grip area. This would work well and the right handed thread will keep it tight. You could use red locktite to ensure that the starter doesn't break it loose. This stuff requires heat to remove.

Dave